Norris 1989.

Study characteristics
Methods	Study design: split‐body, randomised, double‐blinded, double‐paired, controlled trial to evaluate increasing concentrations of polidocanol Method of randomisation: not mentioned Blinding: patient ‐ yes, treating doctor ‐ yes Power calculation: not stated Number of patients randomised: 20 (4 quadrants of each patients's lower limbs) Number of patients analysed: 16 Number of exclusions post randomisation: 0 Number of withdrawals and reasons: 4 Source of funding: not stated
Participants	Setting: outpatient centre Country: USA Total number: 20 Age: range from 30 to 57 years old Sex: female Inclusion criteria: "bilaterally symmetric telangiectasias of the legs and thighs" Exclusion criteria: history of phlebitis, current hormone, disulfiram or anticoagulant use
Interventions	Each patient's legs were divided into 4 quadrants: 1) treated with polidocanol (POL) 0.25% 2) treated with POL 0.5% 3) treated with POL 0.75% 4) treated with POL 1% All patients wore anti‐embolism elastic stockings with gradient pressure for at least 48 hours after treatment, and for as much as possible 2 weeks thereafter Duration: patients were treated every 4 weeks until vessel disappearance or up to a maximum of 6 visits (24 weeks)
Outcomes	1) Efficacy: treating physician (2 study authors) rating of colour photos taken at baseline and prior to each treatment, rated as poor‐to‐moderate, good, excellent 2) Adverse events: a) itching: rated by patient as none or present b) hyperpigmentation: rated by investigators as none or present c) neovascularisation: rated by investigators as none or present 3) patient satisfaction: dissatisfied, neither satisfied or dissatisfied, satisfied, very satisfied 4) number of treatments to clear each quadrant from 1 to >6
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not mentioned. Unsuccessful in attempt to contact authors.
Allocation concealment (selection bias)	Low risk	"Injections were labelled and coded as an unknown and randomly assigned."
Blinding (performance bias and detection bias) All outcomes	Low risk	States double‐blinded but no further details given.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Explanations were provided for the 4 patients who dropped out, and the reasons provided indicate this was unlikely to impact effect size.
Selective reporting (reporting bias)	Low risk	All specified outcomes were reported.
Other bias	High risk	The study design divides each person's legs into four quadrants to receive separate simultaneous treatments and analysis, and thereby risks bias by carry‐across effect.